Constable is one of the lower ranks in the Toronto Police Force and in Flashpoint. Excluding Gregory Parker, Roland Cray and Troy (Unknown Surname), all other SRU members were Constables (only at the end was Ed Lane promoted to the rank of Sergeant).
In Flashpoint, despite all the SRU members being Constable, each of them have different skill sets and seniority. For example, Ed Lane and later Donna Sabine were Team Leaders, but they still held the rank of Constable. Jules Callaghan was a profiler, deputy negotiator and sniper. Mike "Spike" Scarlatti was an explosives and electronics expert. Sam Braddock was primarily a sniper along with Ed, although Ed was senior to him in terms of leadership and only at the end was Sam promoted to Team Leader.
All SRU Despatchers such as Kira Marlowe were also ranked as Constable.
In reality, the Toronto police force has different tiers/levels of Constable, although that is not stated in Flashpoint (see ).